This entry is our analysis of a study considered particularly relevant to improving outcomes from drug or alcohol interventions in the UK. The original study was not published by Findings; click Title to order a copy. Free reprints may be available from the authors – click prepared e-mail. Links to other documents. Hover over for notes. Click to highlight passage referred to. Unfold extra text The Summary conveys the findings and views expressed in the study. Below is a commentary from Drug and Alcohol Findings.

Milby J.B., Schumacher J.E., Vuchinich R.E. et al.Journal of Substance Abuse Treatment: 2008, 34(2), p. 180–191.Unable to obtain a copy by clicking title? Try asking the author for a reprint by adapting this prepared e-mail or by writing to Dr Milby at jmilby@uab.edu. You could also try this alternative source.

Offering homeless, unemployed people seeking treatment for cocaine dependence access to housing and paid employment if they stay drug-free is a powerful incentive, but adding intensive counselling helps maintain abstinence once the incentives end.

Summary This US trial was one of a series conducted in Birmingham, Alabama with a consistent methodology, each involving homeless men and women generally dependent on cocaine and suffering severe distress but not psychotic, and prepared to enter treatment for their drug problems. The series aimed to disentangle the active ingredients of aiding this difficult-to-treat population to resolve their drug problems and get back on their feet in terms of housing and employment.

The main issue was whether adding day care could further improve outcomes when the participants were already subject to powerful employment/housing incentives. During the 24 weeks these incentives were applied, day care participants were only slightly and non-significantly more likely to be abstinent at any point or to sustain abstinence. But after incentives ended, their abstinence rate declined more slowly than that of incentives-only participants. The result was that on both measures, day care resulted in significantly higher abstinence rates in last year of the study. The authors concluded that for this caseload, employment/housing rewards and punishments on their own were a viable initial intervention, and that intensive day care might be reserved for participants who did not respond well to these contingencies or with co-morbidities such as serious mental illness.

Another US research team has investigated the impact of making employment dependent on abstinence, but among a different population – unemployed patients living in poverty in Baltimore who despite being maintained on methadone continued to inject and used cocaine/crack. They volunteered for a data-entry and keypad skills training/work programme remunerated by shopping vouchers. Half were randomly allocated to have access to the workplace (and therefore to pay) only if they submitted a cocaine-negative urine test. The other half were also tested, but the results made no difference to their access to work. This regimen lasted six months. During that time patients required to be abstinent were less likely to use cocaine or to inject, but non-users were still in the minority. Most continued to use cocaine and probably as a result, they spent far fewer days at work and earned less money than patients not required to be abstinent, who also tended to make greater progress in their training. Also the abstinence gains were transitory. Six months after the programme ended, if anything it was the patients who had not been required to be abstinent who were more likely to be cocaine-free. They were also less likely to be trading sex, sharing injecting equipment, or patronising shooting galleries, though by his stage nearly all the diffidence between the two groups were minor and all were statistically insignificant.

The combined implication of these studies is that among these poor, unemployed, and largely
black
In the US context, commonly a marker of severe relative poverty and disadvantage.
populations enmeshed in illegal drug use, work and housing incentives can help initiate and extend drug-free periods, but intensive support is needed to maximise and maintain the benefits once incentives are withdrawn. Without this, the gains from making housing and work dependent on abstinence rapidly erode, and it is unclear whether the long-term benefits justify disrupting the housing and employment stability of patients subject to the contingencies. This disruption is consequent on requiring abstinence in a population for whom this is a very high hurdle. In the featured study, even with intensive support and after a programme lasting from 7.30am to 4pm four days week plus a half day, by the end of the follow-up period most participants continued to use alcohol or other drugs. It also seems that offering decent, affordable housing, substantial employment assistance, and paid employment itself, but without requiring abstinence, has in the longer term been just as effective as making these benefits contingent on abstinence, though the evidence is sparse.

The featured study faced several challenges common to contingency management programmes. Most studies have only documented the limited
period
Typically 12 weeks.
during which incentives were in place. Through this window, the approach seems very effective. But extending the view to the post-incentive period reveals that participants often quickly reverse towards to their
previous behaviour.
This is not inevitable but it is common, a contrast with approaches like cognitive-behavioural therapy which develop skills and lifestyles in patients which in several studies seem to become more securely embedded as time passes.
This may be partly because impacts are typically limited to the targeted behaviours and/or the targeted drugs. Effectively, people do what is needed to get the rewards or avoid the punishments, potentially leaving other relapse-precipitating features of their lives ready to exert their influence once the programme ends. Overcoming this by extending the intervention may be impractical, and may in any event not work; unlike other interventions, in general the longer a contingency management programme runs, the weaker its effects. Another limitation is that such programmes are most feasible and work best when they target a single drug, yet many patients use several to excess. Targeting all these risks setting the bar so high that many patients do not experience the incentives. Even with simpler regimens, patients commonly qualify for none of the rewards or are subjected to sanctions because they do not exert the required control over their behaviour. The risk is that the most vulnerable, unstable and severely dependent participants are further disadvantaged, either missing out altogether or being repeatedly 'knocked back' as they fail to sustain the required standards.

Other studies have attempted to mitigate these risks by enabling incentives to be earned through smaller steps, rewarding recovery-promoting activities rather than or as well as abstinence, and by combining contingency management with programmes which address the individual's psychological or social vulnerabilities. The featured study tried several of these tactics. Within the contingency management regimen, recovery-promoting vocational and employment-related activities were financially rewarded, while psychosocial vulnerabilities were addressed by pairing the incentives with intensive day care. Whether the more severely dependent or unstable patients were relatively disadvantaged is not reported. We know from an earlier study in the series that a quarter of the participants offered intensive day care and housing/employment incentives did not control their substance use sufficiently to qualify for any rewards.

If contingency management does become prevalent in Britain, much will depend on the particular form it takes. The evidence is strongest for rewarding desired behaviour and this is the approach staff and patients may be most comfortable with, but it risks a public and media backlash. Punishing undesired behaviour is less effective and risks counterproductive side effects, but may be more acceptable to the broader public. Another alternative is to reward good behaviour by removing punishments, but this has not been adequately researched.

Thanks for their comments on this entry in draft to Tim Leighton of Action on Addiction's Centre for Addiction Treatment Studies. Commentators bear no responsibility for the text including the interpretations and any remaining errors.